cel troubles. 97 limited 4wd

[CatchM3]

OK so i'm new here but i'm new to the forum scene. i got my 4runner back in December since then its been a great vehicle. i found records for it stating that it had the timing belt replacement at 105000 i'm at 172000 getting close but not there. about every ten days it doesn't want to start. sometimes more frequently than others. i put the key in turn the switch and nothing happens. just a single "click", antenna motor hums. it acts like the starter. but then i put jumper cable on it and it jumps off fine 9 out of ten times. i get in this morning running late and it wont start. so i jump it off no issue. my CEL came on so conveniently i have my scan tool with me plug it in at the red light. turn on my app on my phone. i'm reading codes "p0335" "0340" both relating to the crankshaft position sensor bank 1.

from the research i've gathered this could mean the sensors bad. the wires are bad. or i've jumped time. would this also be the cause of my starting issue or do need to tackle my starter problem then work my way back to up to the crankshaft position sensor. it would suck to put the starter on and find out i need the sensor or timing belt. just looking for a little insight.

 

[jakknz]

You can take the timing belt cover off to check the timing for your two camshaft sprockets to see if it has jumped teeth. Just rotate your crankshaft manually until the timing marks of both sprockets align at the 12 o'clock position.

With it not starting and you getting a code for the crankshaft position sensor, I would say the sensor is intermittently faulty. Double check the electrical connection, clean it out with compressed air and insure it snaps back together correctly and see if that helps.

A good thread to look at with detailed pics of all timing components: http://www.nwtoys.com/forum/tech-article-submissions/1261-5vz-fe-timing-belt.html